In this application for a three-year Fogarty International Award, we will compare HPV infection and other lifestyle factors as risks of oral cancer in the Czech Republic to those of the Iowa population (parent grant). The specific aims of the Fogarty grant are to: 1. Determine the prevalence of HPV DNA in oral cytology specimens of oral cancer cases and age-frequency matched controls as evidence of current HPV infection and assess HPV infection and other, lifestyle factors as a risk factor for oral cancer in the Czech Republic in comparison to similar data in Iowa. 2. Assess the presence, expression and integration of HPV genes in cancers and genetic changes in cellular tumor suppressor gene pathways (p53, p14-ARF, and INK4A) in HPV+ and HPV- tumors in the Czech Republic in comparison to similar data in Iowa. 3. Determine whether "ever" HPV infection is a risk for the development of oral cancer in general, including HPV- oral carcinomas. The association between infection with mucosal oncogenic HPV types and oral carcinogenesis will be better understood by including an additional approach to HPV diagnosis: the detection of anti-HPV antibodies in serologic assays as evidence of history of HPV infection. Evidence of past infection as detected by seropositivity for antibodies against HPV virus-like particles (VLPs) will be correlated with the detection of present HPV infection in the oral cavity by HPV DNA analysis in cytologic specimens and tumors. The Czech lab has unique qualifications in HPV serology research and development, which is still evolving, and in its application to human studies. Their serology assessment of patients for oral cancer risk associated with HPV will enhance the potential findings and would be one of the first groups to do so for oral cancer. They also will provide a uniquely different population from that of Iowa for the study of risks and potentially HPV prevalence associated with oral cancer.